Fe掺杂ZnO纳米线电子性质和磁性质
Electronic and magnetic properties of Fe-doped ZnO nanowires

本文采用第一性原理密度泛函理论系统的研究了Fe原子单掺杂和双掺杂ZnO纳米线的电子性质和磁性质。所有掺杂纳米线的形成能都比纯纳米线的形成能低，说明掺杂过程是放热的。计算结果显示Fe原子趋于占据纳米线表面位置。纳米线的总磁矩主要来源于Fe原子3d轨道的贡献。由于杂化，相邻的O原子也产生了少量自旋。在超原胞内，Fe、O原子磁矩平行排列，表明它们之间是铁磁耦合。表面掺杂纳米线显示出半导体特性；而中间掺杂纳米线显示出半金属性，在自旋电子学领域有广泛应用。
The electronic and magnetic properties of ZnO nanowires doped with one and two Fe atoms are comparatively studied in terms of the first-principles calculation. The formation energies of doped nanowires are smaller than those of the pristine ones, indicating that the doping process is an exothermic reaction. The result shows that Fe atom prefers to the surface position. The magnetic moments are mainly contributed by the Fe-3d orbital. Due to the hybridization interaction, a small magnetic moment is also induced in nearest neighboring O atoms. The magnetic moments of the Fe and O atoms have the same direction, indicating ferromagnetic coupling between them. Surface doped nanowire is semiconductor, while middle doped nanowire is half-metalic, which have important applications in spintronics